Liquid chromatography pumping system with compensation means for liquid compressibility
Nonreactive inlet splitter for gas chromatography and method
High pressure liquid chromatography system
Carrier composition control for liquid chromatographic systems
ApplicationNo. 393449 filed on 02/23/1995
US Classes:417/313, COMBINED137/114, One inflow supplements another137/512, Plural137/550, Planar strainer normal to flow path137/565.33, Parallel137/860, Annulus366/273, Magnetic stirrer417/415Reciprocating rigid pumping member
ExaminersPrimary: Thorpe, Timothy S.
Assistant: Korytnyk, Peter
Attorney, Agent or Firm
Foreign Patent References
International ClassesF04B 039/10
AbstractAn improved mixing unit and check valve for a fluid pumping system wherein gradient proportioning is performed at high pressure are described. The mixing unit has lining means disposed on the inner surface of the chamber for preventing frictional contact between the steel of the chamber and the surface of the rotor. The lining means is formed of a polymeric material selected for frictional compatibility with the rotor, and avoids formation of undesirable particulates by friction with the rotor surface. The check valve has a poppet comprising a midsection dimensioned to provide forward and rearward surfaces against which fluid flow will exert force, a first arm extending transversely from the midsection first side toward the valve inlet, a second arm extending transversely from the midsection second side toward the valve outlet, and first and second resilient seals respectively annularly disposed about the first and second arms. The resilient seals are formed of a resiliently compressible material, and have an uncompressed thickness which is somewhat greater than the first arm length.